ANTENTOP- 01- 2007, # 009

Simple SWL HF- VHF Receiver

C9: 0.05 uF

C10: Variable, air dielectric, 2- 15 pF

C11: Variable, air dielectric, 2- 15 pF

C12: 1.5 pF

C13: 4700 pF

C14: 3300 pF

C15: Variable, air dielectric, 2- 15 pF

C16: 5.0 uF/ 10V

C17: 5.0 uF/ 10V

C18: 20.0 uF/ 12V

Polarized capacitors are electrolytic

Diodes:

VD1- VD4: Any small low power RF Shottky diodes

VD5: Zener diode 9.0V/15 mA

Transformers:

TP1, TP2: Core: Amidon analog is T37- 10

10 turns by trifilar insulated wire OD 0.15 mm

(34 AWG), one winding to 1 cm length.

Uniformly onto the core.

So, primaly winding 1- 10 turns, secondary

winding 2- 10 turns, third winding 3- 10 turns.

●winding phase

TP3: Audio transformer from an old transistor radio

Note: Diodes VD1- VD4 and transformers TP1 and TP2 may be changed to IC SBL-1.

Transistors:

VT1: Small power RF germanium transistor, gain 80- 100, upper frequency 250 MHz

May be changed to silicon transistor with equal data.

VT2: Small power RF germanium transistor, gain 80- 100, upper frequency 250 MHz

May be changed to silicon transistor with equal data.

VT3, VT4: Any high gain (100- 200) small power transistors

Switch:

S1: Any Toggle DPDT

RF Choke

RFC: OD: 3.5... 5 (not critical)mm

Length of winding: 15... 20 (not critical)mm

Coiled by insulated wire OD 0.15 mm (34 AWG)

Winding: Turn to turn, uniformly

73! I.G.

From forum QRP- ARCI (QRP- F- Forum)

Posted by:  John AE5X,

Posted On:  07/15/07,

Subject:  Russian woodpecker antenna

From UA0AAM here is the antenna used at one of the radar sites that we copy on the ham bands at times. I'd sure love to have this baby on 40m some winter evening. I wonder if it's rotatable...?

http://www.antentop.org/

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